Verville T D, Huycke M M, Greenfield R A, Fine D P, Kuhls T L, Slater L N
Medical Service, Department of Veterans Affairs Medical Center, Oklahoma City, Oklahoma.
Medicine (Baltimore). 1994 May;73(3):119-32. doi: 10.1097/00005792-199405000-00001.
Increased recognition of Rhodococcus equi as a human pathogen has occurred since 1983, when the first review article summarized the world's literature of 12 cases. In this article, we present 12 cases from the University of Oklahoma Health Sciences Center and review 60 from the literature. Most cases occur in immunocompromised hosts and present as chronic cavitary pneumonias. Associated extrapulmonary disease is seen at diagnosis in 7% of patients with pneumonia, and relapse occurs at extrapulmonary sites in 13%, often without reappearance of pulmonary disease. Relapse may follow a course of antimicrobial therapy that is too brief, but can also occur during treatment. Infections also occur in the gastrointestinal tract, causing enteritis and regional adenitis with abscesses. Contaminated wounds may become infected. Isolated bacteremias may be a manifestation of latent infection recurring during a period of immune suppression. A common feature of human R. equi infection is delay in diagnosis. The insidious course of disease contributes to delay, as does failure to identify the organism. R. equi is easily cultured on nonselective media but commonly mistaken for a diphtheroid or occasionally for a mycobacterium based on acid-fast appearance. Form and duration of treatment are closely related to host immune status. Immunocompromised patients require prolonged or indefinite therapy with multiple antibiotics. Infections in immunocompetent hosts are easily treated with short courses of single agents. Infections related to contaminated wounds are treated primarily by irrigation and debridement. Infections in immunocompromised hosts are increasing in frequency largely due the AIDS epidemic. Infections in immunocompetent hosts, reported rarely before this series, may be underdiagnosed, perhaps because R. equi resembles common commensals and has limited virulence in this population. This report demonstrates that R. equi infections, including community-acquired pneumonias, occur in immunocompetent hosts.
自1983年以来，马红球菌作为一种人类病原体越来越受到关注，当时的第一篇综述文章总结了全球12例相关文献。在本文中，我们介绍了俄克拉荷马大学健康科学中心的12例病例，并对文献中的60例进行了回顾。大多数病例发生在免疫功能低下的宿主中，表现为慢性空洞性肺炎。7%的肺炎患者在诊断时伴有肺外疾病，13%的患者在肺外部位复发，且肺部疾病通常不再出现。复发可能发生在抗菌治疗疗程过短之后，但也可能在治疗期间出现。感染也可发生在胃肠道，引起肠炎、局部腺炎及脓肿。污染伤口可能会被感染。孤立性菌血症可能是潜伏感染在免疫抑制期复发的表现。人类马红球菌感染的一个共同特征是诊断延迟。疾病的隐匿病程以及未能识别该病原体都会导致诊断延迟。马红球菌很容易在非选择性培养基上培养，但基于抗酸外观通常会被误认为是类白喉杆菌，偶尔也会被误认为是分枝杆菌。治疗的形式和持续时间与宿主免疫状态密切相关。免疫功能低下的患者需要用多种抗生素进行长期或不定时治疗。免疫功能正常的宿主感染用单一药物短疗程治疗很容易治愈。与污染伤口相关的感染主要通过冲洗和清创来治疗。免疫功能低下宿主的感染频率在很大程度上因艾滋病流行而增加。免疫功能正常宿主的感染在此系列报道之前很少见，可能诊断不足，这可能是因为马红球菌与常见共生菌相似，且在该人群中的毒力有限。本报告表明，马红球菌感染，包括社区获得性肺炎，也会发生在免疫功能正常的宿主中。
